Open-hearth furnace



'F. B. McKUNE.

OPEN HEABTH FURNACE.

APPUCATION mm on. 27. I919.

Patented May 11, 1920.

3 SHEETSSHEET I.

ATTORNEYS F. B. McKUNE.

OPEN HEARTH FURNACE.

APPLICATION man 007.21, I919.

INVENTOR IBJIAEzqne F. B. McKUNE. OPEN HEARTH FURNACE APPLICATION FILED ocnzi. 1919.

1,339,855. Patented May 11, 1920.

3 SHEETS-SHEET 3- I i I FRANK BLIBD HOKUNE, 0]! HAMILTON, ONTARIO, CANADA.

OPEN-HEABTH FURNACE.

Specification of Letters Patent.

Patented May 11, 1920.

Application filed October 27, 1918. Serial No. 883,768.

To all whom'z'tma concern:

Be it known that I, FRANK Baum Mo'- KUNE, a citizen of the Dominion of Canada residing at Hamilton, in the Province of bntario and Dominion of Canada, have invented certain new and useful Improvements in Open-Hearth Furnaces, of which,

the following is a specification.

This invention, which relates generally, to improvements in open hearth furnaces, more particularly has for its object to provide certain improved structural arrangements in furnaces of the character referred to, especially adapted for the economical burning of gases, a more uniform distribution thereof and for lengthening the life of the furnace and the checker Work that constitutes a part thereof.

Another and "essential object of my invention is to provide-- in an open hearth furnace, certain improved features adapted for increasing the rapid melting of the heat and which give absolute control of the flame in such furnace, with a material productive increase over the method generally utilized for heating gases.

With other objects in View, my invention, in its subordinate features, embodies certain improvements in the damper rigging that controls the air induction and eduction and in such manner that little or no gas is lost, when reversing the furnace,

and very little dirt carried down through the regenerators, due to a perfect combustion of the gases.

In setting forth the improved details of construction of my open hearth furnace, the purpose of my invention will be best understood by referring to the accom any: ing drawings which i ustrate a pre erred form of my invention, it being premised, however, that various changes in the details or modifications of the'coiiperative arand the scope of my invention as de ed. in the appended claims. In the drawings 0 an other on rangement of the parts shown may be readily made without departing from the s int Figure 1 is a horizontal section open hearth furnace embodying my inventlon, the damper operating mechanism at both ends being shown in plan view, the damper at one end (the inlet) being shown as wholl closed and the damper at the (the outlet) being shown as wholly opened.

. rangement of the serve as inlets and the damper rigtgmg mechanism, hereinafter specifically re erred to.

Fig. 4 is a horizontal section of one end of the furnace taken substantially on the line 4-4 on Fi 3.

Fig. 5 is aetail sectional view of one of the control valves or dampers, and the hydraulic cylinders and lever connections 00- operatively joined therewith, the latter be- 111 in side elevation.

n the drawings, I- have illustrated a conventional form of open hearth furnace in which is embodied my invention and in the showing thereof, see particularly Figs. 1 and 2,'11 designate the usual wet or dry ports, one at each end, into which the gases are delivered in any suitable manner, preferably by gas tunnels 2-2, which extend transversely into the opposite sides of the .furnace walls and which communicate,

through the jet outlets 20-20, with the gas ports 11 and which connect, at their outer sages 14, presently again referred to, are

closed, the entire air can be put throu h the inletport 1 and such air can be either orced or natural air.

By referring now more particularly to Figs. 1 and 4, it will be observed that a supplemental air passage (14 is located at each side of the gas .ports 11 and their air ports 10 10, it being. understood that the arthe supplemental air ports and the control mechanism, presently explained, are alike, so that, when reversing the ports at one end,

ports at the opposite ends as, the outlets and vice versa.

In the complete assemblage of the parts, comprised in my construction of open hearth"furnace, is included hydraulic damper riggi devices, which, per 86, constitut an essentia feature of my invention.

Asis best shown in Figs. 1 and 2, the damas, the main air ports, I 100' per rigging consists of damper doors 7-7, one for each supplemental air passage 44 and the said doors are slidably mounted be tween pipes 8-8 that extend through openings 9-9 in the end walls of the furnace and into the bridge wall portion 11-11, the said pipes constituting runners between which the doors 77 move as they are shifted to their open and closed position in the manner presently explained. a

As is clearly shown in Figs. 1 and 2, the runners or guides 8-8 extend some distance beyond the end walls to provide rest portions on which the doors when shifted to the open position, as indicated at the left of Fig. 2.

Each damper or cut off door I? is provided with an outwardly extended mber and each of the members 70 has a slotway 71 into which is received the lower end of a lever 12 secured at the upper end on a shaft 13 that is journaled in suitable bearing brackets 1414 attached to and projected from the end walls of the furnace.

'The shaft 13, midway its length, has a crank member hereinafter termed the cylinder lever 15, with which joins a vertically reciprocable shaft 16 that connects with the pistons of a pair of hydraulic cylinders 1717, suitably mounted'over the outer face of. each end wall and which include the alternately operating intake and outlet pipes 18, which, in practice, are connected up in any well known manner with a fluid supply for actuating the cylinder pistons for shifting the dampers 7-7, at predetermined times, for reversing the furnace.

While I have s ecifically mentioned hydraulic c linders or actuating the devices that shi t the dampers to the wholly or partly open or closed positions, it is tobe understood that the operation of the dampers or doors H can be done by hydraulicsteam, electricity or compressed air with the control of the same absolutely under the furnace operator.

40 designate cooling pipes that enter through the sides of the furnace adjacent the gas tunnels.

From the foregoin description taken in connection with the rawings, the com lete arrangement, the manner 0 usi an the advantages of'my invention will e readily apparent to those familiar with the operation or use of furnaces of the type referred to.

It. is to be understood that while the entire air can be directed through-the passa s to the gas ports 11, yet in case it is esired that a portion of the air go over the top, it is only a matter of opening the 7 are received,

. only necessary ferring to the drawings that, when the dampers in the supplemental air passages 4-4 are open, the air-continues up alon the assages over the arched to throug Whic the gas ports pass and are ischarged directly under the top of the hearth;

To (give the necessary area that may be desire the dampers at the outgoing end of the furnace are pulled open their entire len h, as shown.

y controlling the air and gas supply in the manner stated, it increases the yield of the heat at least two per cent, due to gettin the air thoroughly mixed with the gases be ore heating the metal. a

With the dampers, before referred to, ar-

ranged as shown and described, it is pos- In my improved furnace, it is, made possible to work gases, that could not, so faras I know, be controlled on the open hearth furnace due to their lightness and lack of control of velocity.

In the working of my construction of furnace, there is no free am going into the furnace except throu h the passages 1.

The working 0 any gas burning furnace is improved, since there is no loss of gas in reversing, which'is customary on a reverberating furnace.

In my furnace, the gas enters the port and is completely cut off before reversing the furnace.

The flow of gases in my furnace can be changed without stopping the furnace and the cost of repairs is very much less than is usual in other types of like furnaces, due to the perfect control and complete combustion of t e gases.

Further, in my construction of liqui time.

My imfprovements may be readil applied to any 0 the conventional types of furnaces fuel or any two gases at the same and, in building new furnaces, it would be to have two regenerators inl stead of four.

Furthermore, in the 1practical use of my invention no g es are furnace, it is ossible to work in any combination of 115 ost in reversing the furnace and asovery little dirt carried down throu h the regenerators, due to the'- perfect com ustion obtained from the gases.- Another and important advantage in the use .01 damper controls arranged as shown and described, is, that since it is necessary to be able to concentrate the gas and air through the one port on the incoming end of the furnace, this can be only effectively done by the use of my dampers and valves.

If this were done without the use of valves arranged as in my construction, it would be impossible to get the velocity on the gas and air which is necessary to get the combustion and effects brought about by ha proper manipulation of my damper device.

By having the dampers so that one can open them on the outgoing end of the furnace, by doing so gives the full area of the dampers and the stack. otherwise the draft on the furnace would be checked.

In the use of my special arrangement of valve and damper mechanism, it brings about a great saving, when reversing the valves as no gas passes through the reversing valves whatever.

The advantage of this feature of'my invention will be apparent, whenit is understood that 15% of the gas required to run the furnace is lost in the reversing of the furnace.

What I claim is:

1. An open hearth furnace having a hearth, a gas port at each of the opposite ends, an air channel that connects with each gas port, a supplemental air channel at each end that discharges into the top of the furnace, damper controls for opening and closing the said supplemental air channels and means for supplying gas to the gas ports.

2. An open. hearth furnace having a hearth, a main air port and a supplemental air port at each end thereof, the main air port being arranged to discharge over the bed or hearth, the supplemental air port being arranged over the closed top of the main air port and to discharge along the top of the furnace, means for supplying gas alternately to the main air ports at either end adjacent their discharges into the furnace, a damper in each of the supplemental air ports, and means for opening and closing said dampers for reversing the direction of the air and gas supply to the furnace.

3. An open hearth furnace having a hearth, a gas port at each of the opposite ends, an air channel that connects with each gas port, supplemental air channels at each end that discharge into the top of the furnace, damper controls for opening and closing the said supplemental air channels and means for supplying gas to the gas ports.

4. In an open hearth furnace in which is included a main air port that discharges onto the hearth, a gas supplying port in connection with the said main air port adjacent the discharge end of the said air port, a pair of supplemental air ports that extend vertically, one at each side of the main air port and which discharges along the crown of the furnace, a damper in each supplemental air port for opening and closing the saidport and means for adjusting the said dampers.

5. In an open hearth furnace in which is included a main air port that discharges onto the hearth, a gas supplying port in connection with the said mam air port adjacent the discharge end of the said air port, a pair of supplemental air ports that extend vertically, one at each side of the main air port, and which discharges along the crown of the furnace, a damper in each supplemental air port for opening and'closing the said port and means for adjusting the said dampers, said means including a rotative shaft, a lever for each damper attached to the shaft and means for imparting reverse rotation to the shaft for adjusting the said dampers to open and close the port.

6. In an open hearth furnace in which is included a main air port that discharges onto the hearth, a gas supplying port in connection with the said main air port adj acent the discharge end of the said air port, a pair of supplemental air ports that extend vertically, one at each side of the main air port, and which discharges along the crown of the furnace, a damper in each supplemental air port for opening and closing the said port and means for adjusting the said dampers, the said last mentioned means comprising a rigging that consists of arock shaft, link connections that join the. dam pers to the shaft and means for rocking the shaft.

7. In an open hearth furnace, in which is included a main air port that discharges onto the hearth, a gas tunnel in communication with the said air port, a gas supply in communication with the tunnel, a supplemental air port that passes adjacent and is adapted for coolin the main air port, a guideway that exten s horizontally across the supplemental air port, a damper slidably mounted in the said guide way and adapted for opening and closing the supplemental air port, the said air port being arranged for conveying air over the crown of the furnace for cooling and for intermixing with the air and gas from the main air port, means for slidably actuating the damper, the said means including arock shaft, a lever arm that connects the shaft and the damper, and means for rocking the shaft, the said means comprising a pair'of hydraulic cylinders, a rod connecting the working pistons of the two 0 linders, and a connection that joins the sai rod and the shaft for rocking the said shaft in revers directions, asthe piston rod is reciprocated at times.

FRANK BAIRD MoKUN E. 

